The present invention relates to filtration and coalescer devices, and in particular to a pleated single phase filter coalescer element and method for removing contaminates from lubricants, fuels and other oil based industrial liquids.
Filtering and coalescing devices for oil based industrial fluids, such as petrochemicals in the nature of gasoline, diesel fuel, turbine oil, gear oil, hydraulic fluid, lubricating oil, etc., organic and/or vegetable oils, fuels, etc., as well as synthetic based lubricants and the like, are well known in the art. Contaminants, including particulate, water, and other foreign substances, must be removed from these industrial fluids to ensure proper long term operation and protection of the associated equipment. For example, to achieve long term, predictable and profitable performance from turbines and turbine driven equipment, the lubrication must be both water-free and particulate-free. Oil conditioning systems are used in preventing lubricant oxidation and viscosity breakdown which set the stage for equipment failure due primarily to metal to metal contact between moving parts of the machinery. Preferably, oil conditioning systems quickly and efficiently remove harmful water, particulate and other contaminates from turbine lubrication oils, and other similar industrial fluids.
Prior filtration devices, such as those disclosed in U.S. Pat. Nos. 6,422,396 and 6,569,330, typically have a two phase filter coalescer, which uses a pleated inner pre-filter to first filter particulate from the liquid, and a cylindrical outer sleeve or bun coalescer to remove water from the pre-filtered liquid. While such devices are generally effective, they have a rather complicated construction, provide significant resistance to fuel flow through the system, and do not always remove enough free and emulsified water from the liquid to meet the ever-increasing specifications required by modern industrial equipment.
Hence, a filter coalescer having an uncomplicated construction, with reduced resistance to fluid flow and increased effectiveness in removing both particulate and emulsified water from the liquid would be clearly beneficial.